docstr: The prefix token for models that uses the GPT-2 tokenizer is the end of text token.
docstr_tok: ["The","prefix","token","for","models","that","uses","the","GPT-2","tokenizer","is","the","end","of","text","token","."]
code: def prefix_token(self) -> str:
      """The prefix token for models that uses the GPT-2 tokenizer is the end of text token."""
      return self.end_of_text_token
  
file_path: H2O/h2o_hf/helm/src/helm/benchmark/window_services/gpt2_window_service.py
imports: from .local_window_service import LocalWindowService
  from .tokenizer_service import TokenizerService
label_desc: Use image node_id 6 for calling the GPT2WindowService obj's underlying member method code with example usage: obj.prefix_token() and returns: self